import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Calendar;
import java.util.GregorianCalendar;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class Cal extends JPanel {
  /** The currently-interesting year month day */
  private int yy, mm, dd;

  /** The buttons to be displayed */
  protected JButton labs[][];

  /** The number of day squares to leave blank at the start of this month */
  protected int leadGap = 0;

  /** A Calendar object used throughout */
  Calendar calendar = new GregorianCalendar();

  /** Today's year */
  protected final int thisYear = calendar.get(Calendar.YEAR);

  /** Today's month */
  protected final int thisMonth = calendar.get(Calendar.MONTH);

  /** One of the buttons. We just keep its reference for getBackground(). */
//  private JButton b0;

  /** The month and year choice */
  private JComboBox monthChoice, yearChoice;
  
//  private String curSel;
  
  private int selDay, selMonth, selYear;
  
  
/**
   * Construct a Cal, starting with today.
   */
  Cal() {
//    super();
    setYYMMDD(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH),
        calendar.get(Calendar.DAY_OF_MONTH));
    buildGUI();
    recompute();
  }

  /**
   * Construct a Cal, given the leading days and the total days
   * 
   * @exception IllegalArgumentException
   *                If year out of range
   */
  Cal(int year, int month, int today) {
//    super();
    setYYMMDD(year, month, today);
    buildGUI();
    recompute();
  }

  private void setYYMMDD(int year, int month, int today) {
    yy = year;
    mm = month;
    dd = today;
    selYear = yy;
    selMonth = mm + 1;
    selDay = dd;
  }

  String[] months = { "January", "February", "March", "April", "May", "June",
      "July", "August", "September", "October", "November", "December" };

  /** Build the GUI. Assumes that setYYMMDD has been called. */
  private void buildGUI() {
    getAccessibleContext().setAccessibleDescription(
        "Calendar not accessible yet. Sorry!");
    setBorder(BorderFactory.createEtchedBorder());

    setLayout(new BorderLayout());
    JPanel tp = new JPanel();
    tp.add(monthChoice = new JComboBox());
    
    for (int i = 0; i < months.length; i++)
      monthChoice.addItem(months[i]);
    monthChoice.setSelectedItem(months[mm]);
    
    monthChoice.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent ae) {
        int i = monthChoice.getSelectedIndex();
        if (i >= 0) {
          mm = i;
          // System.out.println("Month=" + mm);
          recompute();
        }
      }
    });
    monthChoice.getAccessibleContext().setAccessibleName("Months");
    monthChoice.getAccessibleContext().setAccessibleDescription(
        "Choose a month of the year");

    tp.add(yearChoice = new JComboBox());
    yearChoice.setEditable(true);
    for (int i = yy; i < yy + 10; i++)
      yearChoice.addItem(Integer.toString(i));
    yearChoice.setSelectedItem(Integer.toString(yy));
    yearChoice.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent ae) {
        int i = yearChoice.getSelectedIndex();
        if (i >= 0) {
          yy = Integer.parseInt(yearChoice.getSelectedItem()
              .toString());
          // System.out.println("Year=" + yy);
          recompute();
        }
      }
    });
    add(BorderLayout.CENTER, tp);

    JPanel bp = new JPanel();
    bp.setLayout(new GridLayout(7, 7));
    labs = new JButton[6][7]; // first row is days

//    bp.add(b0 = new
    bp.add(new JLabel("Sun"));
    bp.add(new JLabel("Mon"));
    bp.add(new JLabel("Tue"));
    bp.add(new JLabel("Wed"));
    bp.add(new JLabel("Thu"));
    bp.add(new JLabel("Fri"));
    bp.add(new JLabel("Sat"));


    ActionListener dateSetter = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        String num = e.getActionCommand();
        if (!num.equals("")) {
          // set the current day highlighted
          setDayActive(Integer.parseInt(num));
          

//          setCurSel(new String(Integer.parseInt(num) + "-" 
//+ (monthChoice.getSelectedIndex()+1) + "-" + yearChoice.getSelectedItem().toString()));
          
          selDay = Integer.parseInt(num);
          selMonth = (monthChoice.getSelectedIndex()+1);
          selYear = Integer.parseInt((String) yearChoice.getSelectedItem());
          
          // When this becomes a Bean, you can
          // fire some kind of DateChanged event here.
          // Also, build a similar daySetter for day-of-week btns.
        }
      }
    };

    // Construct all the buttons, and add them.
    for (int i = 0; i < 6; i++)
      for (int j = 0; j < 7; j++) {
        bp.add(labs[i][j] = new JButton(""));
        labs[i][j].addActionListener(dateSetter);
      }

    add(BorderLayout.SOUTH, bp);
  }

  public final static int dom[] = { 31, 28, 31, 30, /* jan feb mar apr */
  31, 30, 31, 31, /* may jun jul aug */
  30, 31, 30, 31 /* sep oct nov dec */
  };

  /** Compute which days to put where, in the Cal panel */
  protected void recompute() {
    // System.out.println("Cal::recompute: " + yy + ":" + mm + ":" + dd);
    if (mm < 0 || mm > 11)
      throw new IllegalArgumentException("Month " + mm
          + " bad, must be 0-11");
    clearDayActive();
    calendar = new GregorianCalendar(yy, mm, dd);

    // Compute how much to leave before the first.
    // getDay() returns 0 for Sunday, which is just right.
    leadGap = new GregorianCalendar(yy, mm, 1).get(Calendar.DAY_OF_WEEK) - 1;
    // System.out.println("leadGap = " + leadGap);

    int daysInMonth = dom[mm];
    if (isLeap(calendar.get(Calendar.YEAR)) && mm == 1)
//    if (isLeap(calendar.get(Calendar.YEAR)) && mm > 1)
      ++daysInMonth;
    
//	reset all button text
    for (int i = 0; i < 6; i++)
        for (int j = 0; j < 7; j++) {
          labs[i][j].setText("");
        }
    
    // Fill in numbers for the day of month
    for (int i = 1; i <= daysInMonth; i++) {
      JButton b = labs[(leadGap + i - 1) / 7][(leadGap + i - 1) % 7];
      b.setText(Integer.toString(i));
    }
    
    // 7 days/week * up to 6 rows
    for (int i = leadGap + 1 + daysInMonth; i < 6 * 7; i++) {
      labs[(i) / 7][(i) % 7].setText("");
    }

    // Shade current day, only if current month
    if (thisYear == yy && mm == thisMonth)
      setDayActive(dd); // shade the box for today

    // Say we need to be drawn on the screen
    repaint();
    revalidate();
  }

  public boolean isLeap(int year) {
    if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0)
      return true;
    return false;
  }

  /** Set the year, month, and day */
  public void setDate(int yy, int mm, int dd) {
    // System.out.println("Cal::setDate");
    this.yy = yy;
    this.mm = mm; // starts at 0, like Date
    this.dd = dd;
    recompute();
  }

  /** Unset any previously highlighted day */
  private void clearDayActive() {
    JButton b;

    // First un-shade the previously-selected square, if any
    if (activeDay > 0) {
      b = labs[(leadGap + activeDay - 1) / 7][(leadGap + activeDay - 1) % 7];
//      labs[5][6] is never used and selectable
      b.setBackground(labs[5][6].getBackground());
      b.repaint();
      b.revalidate();
      activeDay = -1;
    }
  }

  private int activeDay = -1;

  /** Set just the day, on the current month */
  public void setDayActive(int newDay) {
//	  reset active day
    clearDayActive();

    // Set the new one
    if (newDay <= 0)
      dd = new GregorianCalendar().get(Calendar.DAY_OF_MONTH);
    else
      dd = newDay;
    // Now shade the correct square
    Component square = labs[(leadGap + newDay - 1) / 7][(leadGap + newDay - 1) % 7];
    square.setBackground(Color.red);
    square.repaint();
    activeDay = newDay;
  }
  /**
   * @return the selDay
   */
  public int getSelDay() {
  	return selDay;
  }

  /**
   * @param selDay the selDay to set
   */
  public void setSelDay(int selDay) {
  	this.selDay = selDay;
  }

  /**
   * @return the selMonth
   */
  public int getSelMonth() {
  	return selMonth;
  }

  /**
   * @param selMonth the selMonth to set
   */
  public void setSelMonth(int selMonth) {
  	this.selMonth = selMonth;
  }

  /**
   * @return the selYear
   */
  public int getSelYear() {
  	return selYear;
  }

  /**
   * @param selYear the selYear to set
   */
  public void setSelYear(int selYear) {
  	this.selYear = selYear;
  }

/**
 * @return the yy
 */
public int getYy() {
	return yy;
}

/**
 * @param yy the yy to set
 */
public void setYy(int yy) {
	this.yy = yy;
}

/**
 * @return the mm
 */
public int getMm() {
	return mm;
}

/**
 * @param mm the mm to set
 */
public void setMm(int mm) {
	this.mm = mm;
}

/**
 * @return the dd
 */
public int getDd() {
	return dd;
}

/**
 * @param dd the dd to set
 */
public void setDd(int dd) {
	this.dd = dd;
}


/**
 * @return the curSel
 */
//public String getCurSel() {
//	return curSel;
//}
//
///**
// * @param curSel the curSel to set
// */
//public void setCurSel(String curSel) {
//	this.curSel = curSel;
//}


}